This format is used for storing several types of bitmaps, including animations. MNG allows you to store lossy and lossless images with compression. This format provides you with more options than GIF for saving animated files while keeping the original image size.
PBM is a Portable image in black and white. Can be opened with programs: Adobe Photoshop CS, ACD Systems Canvas 15, ACD Systems ACDSee 17, Newera Graphics Converter Pro, Corel PaintShop Pro X6. File contains 1 bit per pixel. PBM is a kind of file format PPM. And can be readable or binary.